Tennessee Subscriber Answer: Under normal circumstances, if you are going to bill for an assistant surgeon, you will use the same code as the primary surgeon and append modifier -80 (Assistant surgeon). This is not going to work if the obstetrician is billing the global obstetric service or the delivery plus postpartum care because the assistant in this case is not providing any of those extra services.
In this instance, if the obstetrician is billing for global care, for example 59510 (Routine obstetric care including antepartum care, cesarean delivery, and postpartum care), the assistant bills 59514-80 (Cesarean delivery only). If the ob is billing 59515 (... including postpartum care), the assistant should report 59514-80. The only time the two codes are going to match is when the ob surgeon only does the cesarean delivery with no postpartum care. In that case, both would report 59514, and the assistant would add modifier -80.